Microfracture apparatuses and methods

ABSTRACT

Embodiments of apparatuses and methods for microfracture (e.g., forming a plurality of microfractures in a bone to encourage cartilage regeneration).

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/916,242, filed Mar. 3, 2016, which is a national phase applicationunder 35 U.S.C. § 371 of International Patent Application No.PCT/US2014/054680, filed Sep. 9, 2014, which claims priority to U.S.Provisional Application No. 61/881,058, filed Sep. 23, 2013, thecontents of each of which are incorporated by reference in theirentirety.

BACKGROUND 1. Field of Invention

The present invention relates generally to orthopedic treatments, moreparticularly, but not by way of limitation, to devices and methods forcreating microfractures (e.g., in subchondral bone).

2. Description of Related Art

Examples of treatment methods and apparatuses for creatingmicrofractures in bone are disclosed in (1) J. P. Benthien, et al., Thetreatment of chondral and osteochondral defects of the knee withautologous matrix-induced chondrogenesis (AMIC): method description andrecent developments, Knee Surg Sports Traumatol Arthrosc, August 2011,19(8):1316-1319; (2) Thomas J. Gill, M D, et al., The Treatment ofArticular Cartilage Defects Using the Microfracture Technique, Journalof Orthopaedic & Sports Physical Therapy, October 2006, 36(10):728-738;(3) L. de Girolamo, Treatment of chondral defects of the knee with onestep matrix-assisted technique enhanced by autologous concentrated bonemarrow: In vitro characterisation of mesenchymal stem cells from iliaccrest and subchondral bone, Injury, Int. J. Care Injured 41 (2010)1172-1177; (4) Pub. No. US 2009/0143782; (5) Pub. No. US 2005/0043738;(6) Pub. No. US 2005/0021067; and (7) Pub. No. US 2004/0147932.

SUMMARY

This disclosure includes embodiments of apparatuses, kits, and methodsfor creating microfractures in bone (e.g., subchondral bone). At leastsome of the present embodiments are configured to create a microfracturewith a greater depth-to-width ratio than has been possible with knownmethods and apparatuses. For example, some embodiments are configured tocreate a microfracture in subchondral bone having a (e.g., first)transverse dimension (e.g., diameter) of less than 1.2 millimeters (mm)(e.g., between 1 mm and 1.1 mm, less than 1.1 mm, less than 1.05 mm,less than 1 mm), and a depth (or length) of at least 5 mm (e.g., 7 mm, 8mm, 8-10 mm, or the like).

Some embodiments of the present apparatuses comprise: a cannula having afirst end, a second end, and a channel extending between the first endand the second end, the channel having a first transverse dimensionbetween the first end and the second end and having a second transversedimension at the second end that is smaller than the first transversedimension; and a penetrator having a distal end and a first transversedimension, the penetrator configured to be disposed in the channel ofthe cannula such that the penetrator is movable between a retractedposition and an extended position in which the distal end extends beyondthe second end of the cannula by a penetration distance; where thepenetrator is configured to be moved from the retracted position to theextended position substantially without rotation of the penetrator toform in subchondral bone a microfracture. In some embodiments, the firsttransverse dimension is substantially constant along a majority of thelength of the channel. In some embodiments, the cannula has a primaryportion and a distal portion between the primary portion and the secondend, the distal portion configured such that: a second end of thechannel is disposed at an angle relative to a first end of the channel;and the channel has a third transverse dimension at a proximal end ofthe distal portion that is larger than the second transverse dimension.In some embodiments, the third transverse dimension is substantiallyequal to the first transverse dimension.

Some embodiments of the present apparatuses comprise: a cannula having afirst end, a second end, and a channel extending between the first endand the second end, the channel having a transverse dimension at thesecond end; a guide member having an opening and configured to becoupled to the second end of the cannula such that at least a portion ofthe opening is aligned with the channel, the opening having a transversedimension that is smaller than the transverse dimension of the channelat the second end of the cannula; and a penetrator having a distal endand a first transverse dimension, the penetrator configured to bedisposed in the channel of the cannula such that the penetrator ismovable between a retracted position and an extended position in whichthe distal end extends beyond the guide member by a penetrationdistance; where the penetrator is configured to be moved from theretracted position to the extended position substantially withoutrotation of the penetrator to form in subchondral bone a microfracture.In some embodiments, the cannula has a primary portion and a distalportion between the primary portion and the second end, the distalportion configured such that: a second end of the channel is disposed atan angle relative to a first end of the channel, and the channel has athird transverse dimension at a proximal end of the distal portion thatis larger than the second transverse dimension. In some embodiments, thethird transverse dimension is substantially equal to the firsttransverse dimension.

Some embodiments of the present apparatuses comprise: a cannula having afirst end, a second end, and a channel extending between the first endand the second end; a penetrator having a distal end and a firsttransverse dimension, the penetrator configured to be disposed in thechannel of the cannula such that the penetrator is movable between aretracted position and an extended position in which the distal endextends beyond the second end of the cannula by a penetration distance,the penetrator having a guide portion spaced from the distal end, theguide portion having a second transverse dimension that is larger thanthe smallest transverse dimension of the penetrator; where thepenetrator is configured to be moved from the retracted position to theextended position substantially without rotation of the penetrator toform in subchondral bone a microfracture. In some embodiments, thecannula has a primary portion and a distal portion between the primaryportion and the second end, the distal portion configured such that asecond end of the channel is disposed at an angle relative to a firstend of the channel. In some embodiments, the distal portion of thecannula is configured such that the second end of the channel is alignedwith the first end of the channel. In some embodiments, the guideportion includes two segments spaced apart from each other, each segmenthaving a transverse dimension that is larger than the smallesttransverse dimension of the penetrator.

Some embodiments of the present apparatuses comprise: a cannula having afirst end, a second end, and a channel extending between the first endand the second end, the cannula having a primary portion and a distalportion between the primary portion and the second end, the distalportion configured such that a second end of the channel is aligned withand disposed at an angle relative to a first end of the channel; and apenetrator having a distal end and a first transverse dimension, thepenetrator configured to be disposed in the channel of the cannula suchthat the penetrator is movable between a retracted position and anextended position in which the distal end extends beyond the second endof the cannula by a penetration distance; where the penetrator isconfigured to be moved from the retracted position to the extendedposition substantially without rotation of the penetrator to form insubchondral bone a microfracture. In some embodiments, the distalportion of the cannula includes a plurality of curved segments. In someembodiments, the distal portion of the cannula includes a first arcuatesegment extending from a distal end of the primary portion, a secondarcuate segment extending from and curving in a direction opposite tothe curvature of the first arcuate segment, a third arcuate segmentextending from and curving in the same direction as the curvature of thesecond arcuate segment, and a fourth linear segment extending from thethird arcuate segment. In some embodiments, a first longitudinal axis ofthe fourth linear segment intersects a second longitudinal axis of theprimary portion at the second end of the cannula. In some embodiments,the first longitudinal axis intersects the second longitudinal axis atan angle of between 30 and 60 degrees. In some embodiments, the primaryportion of the cannula is substantially symmetrical around alongitudinal axis.

In some embodiments of the present apparatuses, the penetration distanceis at least 5 times greater than the first transverse dimension of thechannel. In some embodiments, the first transverse dimension is lessthan 1.2 millimeters (mm) (e.g., less than 1.1 mm). In some embodiments,the penetration distance is at least 5 millimeters (mm). In someembodiments, the penetrator is configured to be moved from the retractedposition to the extended position substantially without rotation of thepenetrator to form in subchondral bone a microfracture having a depth ofat least 5 mm. In some embodiments, the penetrator is configured to bemanually moved from the retracted position to the extended position. Insome embodiments, the penetrator has an enlarged head, and thepenetration distance is limited by the enlarged head contacting thecannula. In some embodiments, the penetrator comprises an elongated bodyand an enlarged head coupled to the elongated body. In some embodiments,the enlarged head is unitary with the elongated body. In someembodiments, the cannula includes a recessed portion and a shelf, therecessed portion extending from the first end of the cannula toward thesecond end of the cannula, the shelf disposed between the recessedportion and the second end of the cannula such that the penetrationdistance is limited by the enlarged head contacting the shelf. In someembodiments, the recessed portion has a depth that is at least as largeas the penetration distance. In some embodiments, the enlarged head hasa cylindrical shape with a length and a transverse dimension that issmaller than the length. In some embodiments, the enlarged head has atransverse dimension that is at least 90% of a corresponding transversedimension of the recessed portion.

In some embodiments of the present apparatuses, the distal end of thepenetrator is pointed. In some embodiments, the penetrator comprises atleast one of a biocompatible metal, nickel-titanium alloy, stainlesssteel, and 316L stainless steel. In some embodiments, a coating isdisposed on at least the penetration portion of the penetrator. In someembodiments, the coating is hydrophilic. In some embodiments, thecoating comprises silver ions.

In some embodiments of the present apparatuses, the penetrator includesa primary portion and a penetration portion, the primary portion havinga circular cross-section, the penetration portion disposed between theprimary portion and the distal end, the penetration portion having acircular cross-section that is smaller than the circular cross-sectionof the primary portion. In some embodiments, the first transversedimension is in the penetration portion, and a second transversedimension smaller than the first dimension is between the firsttransverse dimension and the primary portion. In some embodiments, thepenetration portion has a length and the second transverse dimension issubstantially constant along part of the length of the penetrationportion. In some embodiments, the penetration portion includes a narrowportion with at least one transverse dimension that is less than anadjacent transverse dimension of the penetration portion, such that thenarrow portion is configured to reduce contact between the penetratorand a bone if the penetration portion is inserted into bone. In someembodiments, the penetrator includes a primary portion and a penetrationportion disposed between the primary portion and the distal end, thefirst transverse dimension is in the penetration portion, and a secondtransverse dimension is between the first transverse dimension and theprimary portion. In some embodiments, the second transverse dimension issmaller than the first transverse dimension. In some embodiments, thepenetration portion has a length, and the second transverse dimension issubstantially constant along part of the length of the penetrationportion. In some embodiments, the first transverse dimension is closerto the distal end than to the primary portion. In some embodiments, thepenetrator has a first cross-sectional area at the first transversedimension, the penetrator has a second cross-sectional area at thesecond transverse dimension, and the first cross-sectional area islarger than the second cross-sectional area. In some embodiments, thepenetrator has a first circular cross section at the first transversedimension, and the penetrator has a second circular cross section at thesecond transverse dimension.

In some embodiments of the present apparatuses, the distal end includesa pointed tip with a cross-sectional shape defined by a tip angle of 60degrees or greater. In some embodiments, the tip angle is bisected by acentral longitudinal axis of the penetration portion. In someembodiments, the tip angle is greater than 90 degrees (e.g., greaterthan 120 degrees).

Some embodiments of the present apparatuses further comprise: apenetrator removal tab coupled to the penetrator and configured toretract the penetrator relative to the cannula. In some embodiments, thecannula includes a handle, the penetrator includes a flange, thepenetrator removal tab includes an opening that is has at least onetransverse dimension that is smaller than a transverse dimension of theflange; and the penetrator removal tab is configured to be disposedbetween the handle and the flange with the penetrator extending throughthe opening. In some embodiments, the penetrator removal tab includes aprotrusion configured to extend toward the second end of the cannula andcontact the handle to act as a fulcrum for pivoting the penetratorremoval tab. In some embodiments, the cannula comprises a handle havingan indicator indicative of the position of the distal portion of thecannula.

Some embodiments of the present apparatuses further comprise: an adapterhaving a first end configured to be coupled to the first end of thecannula, and a second end configured to be coupled to a syringe suchthat the syringe can be actuated to deliver solution to the channel ofthe cannula. In some embodiments, the first end of the adapter includesa tapered outer surface. In some embodiments, the second end of theadapter includes a luer lock. In some embodiments, the adapter has twoor more protrusions configured for manipulation of the adapter.

Some embodiments of the present apparatuses comprise: a cannula having afirst end, a second end, and a channel extending between the first endand the second end, the channel having a first transverse dimensionbetween the first end and the second end and having a second transversedimension at the second end that is smaller than the first transversedimension; a penetrator having a distal end and a first transversedimension, the penetrator configured to be disposed in the channel ofthe cannula such that the penetrator is movable between a retractedposition and an extended position in which the distal end extends beyondthe second end of the cannula by a penetration distance, the penetratorconfigured to be moved from the retracted position to the extendedposition to form in subchondral bone a microfracture; and an adapterhaving a first end configured to be coupled to the first end of thecannula, and a second end configured to be coupled to a syringe suchthat the syringe can be actuated to deliver solution to the channel ofthe cannula. In some embodiments, the first end of the adapter includesa tapered outer surface. In some embodiments, the second end of theadapter includes a luer lock.

Some embodiments of the present adapters comprise: a first end, a secondend, and a channel extending between the first end and the second end,the first end having a tapered frustoconical outer surface configured tocouple with a female receptacle, the second end having a luer lock, andfirst and second protrusions extending from an exterior surface of theadapter between the first end and the second end. In some embodiments,the first end has an inner diameter less than 5 mm. In some embodiments,the first end has at least one outer diameter less than 6 mm. In someembodiments, the first and second protrusions extend at least 3 mm froman exterior surface of the adapter. In some embodiments, the luer lockis configured to be connected to a syringe.

Some embodiments of the present kits comprise: an embodiment of thepresent apparatuses, where the penetrator is a first penetrator; and asecond penetrator configured to be disposed in the channel of thecannula such that the second penetrator is movable between a retractedposition and an extended position.

Some embodiments of the present kits comprise: a first one of thepresent penetrators (e.g., of one of the present apparatuses); and apackage within which the first penetrator is sealed. Some embodimentsfurther comprise: a second penetrator sealed in the package; where atleast one of: the transverse dimension of the second penetrator isdifferent than the transverse dimension of the first penetrator; and thesecond penetration distance is different than the first penetrationdistance. Some embodiments further comprise: an embodiment of thepresent cannulas (e.g., of one of the present apparatuses). Someembodiments further comprise; a tray within which the cannula isdisposed.

Some embodiments of the present kits comprise: an embodiment of thepresent cannulas (e.g., of one of the present apparatuses); a re-usable,sterilizable tray; and a package within which the cannula and tray aresealed. Some embodiments further comprise: an embodiment of the presentguide members (e.g., of one of the present apparatuses).

Some embodiments of the presents kits comprise: an embodiment of thepresent apparatuses; and a package within which the apparatus isdisposed; where the apparatus is sterile.

Some embodiments of the present methods (e.g., of forming amicrofracture in subchondral bone of a patient) comprise: disposing anembodiment of the present microfracture apparatuses adjacent to thesubchondral bone; and advancing the penetrator relative to the cannula,substantially without rotation of the penetrator, until the distal endof the penetrator extends into the subchondral bone to form amicrofracture having a depth greater than 5 mm. Some embodiments furthercomprise: repeating the steps of disposing and advancing to form aplurality of microfractures in the subchondral bone. In someembodiments, the apparatus further comprises a penetrator removal tabcoupled to the penetrator and configured to retract the penetratorrelative to the cannula, and the method further comprises: actuating thepenetrator removal tab to retract the distal end of the penetrator fromthe bone. In some embodiments, the cannula includes a handle, thepenetrator includes a flange, the penetrator removal tab includes anopening that is has at least one transverse dimension that is smallerthan a transverse dimension of the flange; and the penetrator removaltab is configured to be disposed between the handle and the flange withthe penetrator extending through the opening. In some embodiments, thepenetrator removal tab includes a protrusion configured to extend towardthe second end of the cannula and contact the handle to act as a fulcrumfor pivoting the penetrator removal tab, and actuating the penetratorremoval tab includes pivoting the penetrator removal tab around a pointof contact between the protrusion and the handle. In some embodiments,the cannula comprises a handle having an indicator indicative of theposition of the distal portion of the cannula. In some embodiments, themicrofracture apparatus is disposed such that the second end of thecannula contacts the subchondral bone.

In some embodiments of the present methods, the penetrator is advancedmanually. In some embodiments, the position of the second end of thecannula relative to the bone is substantially constant while advancingthe penetrator. In some embodiments, the penetrator has an enlargedhead, and the penetration distance is limited by the enlarged headcontacting the cannula. In some embodiments, the cannula includes arecessed portion and a shelf, the recessed portion extending from thefirst end of the cannula toward the second end of the cannula, the shelfdisposed between the recessed portion and the second end of the cannulasuch that the penetration distance is limited by the enlarged headcontacting the shelf. In some embodiments, the recessed portion has adepth that is at least as large as the penetration distance. In someembodiments, the enlarged head has a cylindrical shape with a length anda transverse dimension that is smaller than the length. In someembodiments, the enlarged head has a transverse dimension that is atleast 90% of a corresponding transverse dimension of the recessedportion. In some embodiments, the distal end of the penetrator ispointed. In some embodiments, the penetrator includes a primary portionand a penetration portion, the primary portion having a circularcross-section, the penetration portion disposed between the primaryportion and the distal end, the penetration portion having a circularcross-section that is smaller than the circular cross-section of theprimary portion. In some embodiments, the first transverse dimension isin the penetration portion, and a second transverse dimension smallerthan the first dimension is between the first transverse dimension andthe primary portion. In some embodiments, the penetration portion has alength and the second transverse dimension is substantially constantalong part of the length of the penetration portion.

In some embodiments of the present methods, the penetrator includes aprimary portion and a penetration portion disposed between the primaryportion and the distal end, the first transverse dimension is in thepenetration portion, and a second transverse dimension is between thefirst transverse dimension and the primary portion. In some embodiments,the second transverse dimension is smaller than the first transversedimension. In some embodiments, the penetration portion has a length,and the second transverse dimension is substantially constant along partof the length of the penetration portion. In some embodiments, the firsttransverse dimension is closer to the distal end than to the primaryportion. In some embodiments, the penetrator has a first cross-sectionalarea at the first transverse dimension, the penetrator has a secondcross-sectional area at the second transverse dimension, and the firstcross-sectional area is larger than the second cross-sectional area. Insome embodiments, the penetrator has a circular cross section at thefirst transverse dimension, and has a circular cross section at thesecond transverse dimension. In some embodiments, the distal endincludes a pointed tip with a cross-sectional shape defined by a tipangle of 60 degrees or greater. In some embodiments, the tip angle isbisected by a central longitudinal axis of the penetration portion. Insome embodiments, the tip angle is greater than 90 degrees (e.g.,greater than 120 degrees).

Some embodiments of the present methods (e.g., of treating amicrofracture in subchondral bone of a patient) comprise: disposing anembodiment of the present (e.g., microfracture) apparatuses with thesecond end of the cannula adjacent an articular surface of a patient;moving the penetrator from the retracted position to the extendedposition to form a microfracture in the articular surface; removing thepenetrator from the cannula; and injecting a solution to themicrofracture through the channel of the cannula. In some embodiments,the solution is injected into the channel through an adapter (e.g., oneof the present apparatuses). In some embodiments, the solution isinjected into the channel from a syringe. In some embodiments, thesolution is injected into the adapter from a syringe.

Some embodiments of the present methods (e.g., of treating amicrofracture in subchondral bone of a patient) comprise: delivering asolution to a microfracture in an articular surface of a patient througha channel of a cannula of one of the present (e.g., microfracture)apparatuses having the second end of the cannula disposed adjacent thearticular surface.

The term “coupled” is defined as connected, although not necessarilydirectly, and not necessarily mechanically; two items that are “coupled”may be unitary with each other. The terms “a” and “an” are defined asone or more unless this disclosure explicitly requires otherwise. Theterm “substantially” is defined as largely but not necessarily whollywhat is specified (and includes what is specified; e.g., substantially90 degrees includes 90 degrees and substantially parallel includesparallel), as understood by a person of ordinary skill in the art. Inany disclosed embodiment, the terms “substantially,” “approximately,”and “about” may be substituted with “within [a percentage] of” what isspecified, where the percentage includes 0.1, 1, 5, and 10 percent.

Further, a device or system that is configured in a certain way isconfigured in at least that way, but it can also be configured in otherways than those specifically described.

The terms “comprise” (and any form of comprise, such as “comprises” and“comprising”), “have” (and any form of have, such as “has” and“having”), “include” (and any form of include, such as “includes” and“including”), and “contain” (and any form of contain, such as “contains”and “containing”) are open-ended linking verbs. As a result, anapparatus that “comprises,” “has,” “includes,” or “contains” one or moreelements possesses those one or more elements, but is not limited topossessing only those elements. Likewise, a method that “comprises,”“has,” “includes,” or “contains” one or more steps possesses those oneor more steps, but is not limited to possessing only those one or moresteps.

Any embodiment of any of the apparatuses, systems, and methods canconsist of or consist essentially of—rather thancomprise/include/contain/have—any of the described steps, elements,and/or features. Thus, in any of the claims, the term “consisting of” or“consisting essentially of” can be substituted for any of the open-endedlinking verbs recited above, in order to change the scope of a givenclaim from what it would otherwise be using the open-ended linking verb.

The feature or features of one embodiment may be applied to otherembodiments, even though not described or illustrated, unless expresslyprohibited by this disclosure or the nature of the embodiments.

Details associated with the embodiments described above and others aredescribed below.

BRIEF DESCRIPTION OF THE DRAWINGS

The following drawings illustrate by way of example and not limitation.For the sake of brevity and clarity, every feature of a given structureis not always labeled in every figure in which that structure appears.Identical reference numbers do not necessarily indicate an identicalstructure. Rather, the same reference number may be used to indicate asimilar feature or a feature with similar functionality, as maynon-identical reference numbers. The figures are drawn to scale (unlessotherwise noted), meaning the sizes of the depicted elements areaccurate relative to each other for at least the embodiment depicted inthe figures.

FIG. 1A depicts a perspective view of a first embodiment of the presentapparatuses having a cannula and a penetrator, with the cannula shownnext to the penetrator.

FIG. 1B depicts a cross-sectional view of the apparatus of FIG. 1A, withthe cannula shown next to the penetrator.

FIG. 1C depicts a cross-sectional view of an enlarged head of thepenetrator shown in FIG. 1A.

FIG. 1D depicts a cross-sectional view of a first end of the cannulashown in FIG. 1A.

FIG. 2A depicts a perspective view of the apparatus of FIG. 1A, with thepenetrator shown in the cannula.

FIG. 2B depicts a cross-sectional view of the apparatus of FIG. 1A, withthe penetrator shown in the cannula.

FIG. 2C depicts a cross-sectional view of a portion of the apparatus ofFIG. 1A that includes a second end of the cannula and a distal end ofthe penetrator, with the penetrator shown in the cannula.

FIG. 3 depicts a perspective view of a second embodiment of the presentapparatuses.

FIGS. 4A and 4B depict perspective view of the apparatus of FIG. 3positioned for use relative to a patient's knee, and are not drawn toscale.

FIG. 5A depicts a side view of a second embodiment of the presentpenetrators.

FIGS. 5B and 5C depict enlarged side views of a penetration portion ofthe penetrator of the penetrator of FIG. 5A.

FIG. 6 depicts a side cross-sectional view of a second embodiment of thepresent cannulas.

FIG. 7A depicts a side cross-sectional view of a third embodiment of thepresent cannulas.

FIG. 7B depicts an enlarged cross-sectional view of a distal portion ofthe cannula of FIG. 7A.

FIGS. 8A-8C depict various views of handle for use with the presentcannulas.

FIG. 9 depicts an exploded perspective view of a kit comprising anembodiment of the present apparatuses and a package for the apparatus.

FIGS. 10A-10D depict various views of another embodiment of the presentapparatuses that includes a penetrator removal tab in combination withthe penetrator of FIG. 5A and a fourth embodiment of the presentcannulas.

FIG. 11A depicts a cross-sectional view of a portion of a fourthembodiment of the present cannulas.

FIG. 11B depicts a cross-sectional view of a portion of the cannula ofFIG. 11A with a penetrator of FIGS. 5A-5C disposed in the channel of thecannula.

FIG. 12 depicts a cross-sectional view of a portion of the cannula ofFIG. 7A with a guide member coupled to a distal end of the cannula.

FIG. 13 depicts a cross-sectional view of a portion of the cannula ofFIG. 7A with another embodiment of the present penetrators disposed inthe channel of the cannula.

FIG. 14A depicts a side view of a fifth embodiment of the presentcannulas.

FIG. 14B depicts an enlarged side view of the cannula of FIG. 14A.

FIG. 15A-15B depict perspective views of a sixth embodiment of thepresent apparatuses shown with an adapter for coupling a syringe to thecannula of the apparatus.

DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

Referring now to the drawings, and more particularly to FIGS. 1A-2C,shown therein and designed by the reference numeral 10 is one embodimentof the present apparatuses for creating microfractures in bone (e.g.,subchondral bone). In the embodiment shown, apparatus 10 comprises apenetrator 14, a cannula 18, and a handle 22 coupled to cannula 18. Inother embodiments (e.g., as shown in FIG. 3), handle 22 may be omitted.In the embodiment shown, cannula 18 has a first end 26, a second end 30,and a channel 34 extending between the first end and the second end.Such first and second ends should be understood as the locations of thebeginning and end of the channel. In this embodiment, cannula 18 has aprimary portion 38 and a distal portion 42, with primary portion 38extending between first end 26 and distal portion 42 (e.g., a majorityof the length of the cannula, as in the embodiment shown), and withdistal portion 42 extending between primary portion 38 and second end30. The distal portion can be configured such that a second end of thechannel (at second end 30) is disposed at an angle relative to a firstend of the channel (at first end 26). For example, in the embodimentshown, distal portion 42 is disposed at an angle 46 relative to theprimary portion. In the embodiment shown, angle 46 is between 10 and 30degrees (e.g., 20 degrees). In other embodiments, angle 46 can be anysize that permits apparatus 10 to function as described in thisdisclosure (e.g., angle 46 can be equal to, or between any two of: 0,10, 20, 30, 40, 45, 50, and/or 60 degrees). In other embodiments, angle46 can be greater than 60 degrees (e.g., equal to, or between any twoof: 60, 70, 80, 90, and/or more degrees). As a further example, distalportion 42 can include a curved or hooked shape such that angle 46 iseffectively larger than 90 degrees (e.g., equal to, or between any twoof: 90, 120, 150, 180, and/or 180 degrees).

Primary portion 38 has a transverse dimension 50 (e.g., a diameter, inthe embodiment shown). Penetrator 14 and cannula 18 can comprise anysuitable material that permits the apparatus to function as described inthis disclosure (e.g., and permits the penetrator and the cannula to besterilized). For example, in some embodiments, penetrator 14 comprisesnickel-titanium alloy (e.g., Nitinol), and/or cannula 18 comprisesmetal, such as stainless steel (e.g., a surgical stainless steel).Embodiments of the present cannulas are rigid and configured not to flexor bend during use. In other embodiments, penetrator 14 can comprise abiocompatible metal such as stainless steel (e.g., 316L stainlesssteel).

In the embodiment shown, penetrator 14 has a proximal end 54, anenlarged head 58 adjacent proximal end 54, a primary portion 62, adistal end 66 (e.g., pointed distal end 66, as shown), and a penetrationportion 70 adjacent distal end 66. In this embodiment, penetrationportion 70 has a length 74 that is a minority of the length ofpenetrator 14 between proximal end 54 and distal end 66. In someembodiments, penetrator 14 has a transverse dimension of less than 1.2mm (e.g., between 1 mm and 1.1 mm; less than 1.1 mm, less than 1.05 mm,less than 1 mm; less than, or between any two of, 0.5, 0.6, 0.7, 0.8,0.9, and/or 1 mm). For example, in the embodiment shown, penetrationportion 70 has a circular cross-section with a diameter 78 of between0.7 and 0.8 mm (e.g., 0.78 mm). In some embodiments, penetration portion70 has a circular cross-section with a diameter of between 1 and 1.1 mm(e.g., 1.04 mm). Penetrator 14 is configured to be disposed in channel34 of cannula 18 such that penetrator 14 is movable between a (1)retracted position (e.g., in which distal end 66 of the penetrator doesnot extend beyond second end 30 of the cannula) and (2) an extendedposition in which distal end 66 of the penetrator extends beyond secondend 30 of the cannula by a penetration distance 82. In some embodiments,penetration distance 82 is at least (e.g., greater than) 5 mm (e.g., 7mm, 8 mm, 8-10 mm, more than 10 mm) and/or at least (e.g., greater than)5 times (e.g., greater than, or between any two of: 6, 7, 8, 9, 10, ormore times) a transverse dimension (e.g., diameter) of penetrator 14(e.g., diameter 78 of penetration portion 70). For example, in theembodiment shown, penetration distance 82 is between 8 mm and 10 mm(e.g., 10 mm), which is greater than 12 times diameter 78. In theembodiment shown, diameter 50 of primary portion 38 is larger thandiameter 78 of penetration portion 70. In some embodiments, diameter 50is also less than 1.2 mm (e.g., between 1 mm and 1.1 mm, less than 1.1mm, less than 1.05 mm). In some embodiments, diameter 50 issubstantially equal to diameter 78. In some embodiments, penetrator 14comprises a central wire defining diameter 78 that is encircled orencased by an outer tubing (e.g., metallic tubing, plastic shrink wrap,and/or the like along the length of primary portion 62 to definetransverse dimension 50.

In some embodiments, a coating is disposed on at least penetrationportion 70 of penetrator 14 (the coating may also be disposed on primaryportion 62 of the penetrator). In some embodiments, the coating ishydrophilic. Examples of hydrophilic coatings include Hydro-Silkcoatings available from TUA Systems of Florida (U.S.A.). In someembodiments, the coating comprises silver ions. In some embodiments, thecoating comprises one or more active ingredients configured to elicit orstimulate a biological response in (e.g., bone or cartilage) tissue,such as, for example, growth factor(s), anticoagulant(s), protein(s),and/or the like. Such coatings can be applied as known in the art forthe materials used in particular embodiments.

In the embodiment shown, cannula 18 is configured to provide lateralsupport for penetrator 14, such as to prevent the penetrator frombending or buckling while being driven into the hard subchondral bone.For example, in the embodiment shown, diameter 50 of primary portion 62of the penetrator is nearly as large as (e.g., greater than, or betweenany two of: 95, 96, 97, 98, 99, and or 100 percent of) the diameter ofchannel 34, and diameter 78 of penetration portion 70 is greater than75% (e.g., greater than, or between any two of: 75, 80, 85, 90, 95,and/or 100 percent of) the diameter of channel 34 (e.g., the diameter ofchannel 34 adjacent second end 30 of the cannula). In some embodiments,penetrator 14 is substantially straight prior to being disposed inchannel 34 of cannula 18, such that inserting the penetrator into thecannula causes the penetration portion 70 of the penetrator to be angledrelative to primary portion 62. In some such embodiments, penetrator 14may be resilient enough to (e.g., at least partially) return to itsstraight shape after removal from the cannula.

In some embodiments, penetrator 14 is configured to be moved or advanced(e.g., substantially without rotation of the penetrator) from theretracted position to the extended position (FIG. 2B) to form amicrofracture in subchondral bone (e.g., in a patient's knee or shoulderjoint), the microfracture having a depth of at least (e.g., more than) 5mm (e.g., 7 mm, 8 mm, 8-10 mm, more than 10 mm) and/or at least (e.g.,greater than) 5 times (e.g., greater than, or between any two of: 6, 7,8, 9, 10, or more times) a transverse dimension (e.g., diameter) ofpenetrator 14 (e.g., diameter 78 of penetration portion 70). Forexample, in the embodiment shown, penetrator 14 is configured to bemoved or advanced (e.g., substantially without rotation of thepenetrator, which includes no rotation up to rotation of less than onefull revolution clockwise and/or counterclockwise from the position atwhich distal end 66 of the penetrator first contacts the bone) from theretracted position to the extended position (FIG. 2B) to form amicrofracture in subchondral bone (e.g., in a patient's knee or shoulderjoint), the microfracture having a depth of between 8 mm and 10 mm(e.g., 10 mm), which is greater than 12 times diameter 78. In theembodiment shown, penetrator 14 is configured to be moved or advancedmanually to the extended position. As used in this disclosure, moved oradvanced “manually” means without the assistance of an external energysource other than that provided by a user. For example, if thepenetrator is moved or advanced with a battery-powered or spring-drivendriver, it would not be “manually.” Conversely, the penetrator would bemoved or advanced “manually” if a mallet, hammer, or other tool is swungby a user (e.g., in the user's hand) to impact first end 26 of thepenetrator. In some embodiments, the present apparatuses are configuredsuch that the penetrator can (but need not) be rotated as it is advancedor moved from the retracted position to the advanced position. Forexample, a portion of the penetrator (e.g., enlarged head 58) can bedisposed in the chuck of a drill such that the drill can rotate thepenetrator. In such embodiments, the penetrator may (but need not) besubstantially straight or axial (without bends) along its entire length(e.g., prior to being disposed in a cannula with an angled distalportion).

In the embodiment shown, penetration distance 82 (and the depth of themicrofracture the apparatus is configured to create) is limited byenlarged head 58 contacting the cannula (e.g., penetration distance ismaximized when enlarged head 58 contacts the cannula, as shown in FIG.2B). For example, in the embodiment shown, cannula 18 includes arecessed portion 86 and a shelf 90. As shown, recessed portion 86extends from first end 26 toward second end 30 (inwardly), and shelf 90is disposed between recessed portion 86 and second end 30 such thatpenetration distance 82 is limited by enlarged head 58 contacting shelf90. For example, in the embodiment shown, enlarged head 58 has acylindrical (e.g., circular cylindrical, as shown) with a first end 94and a second end 98, and is configured such that second end 98 contactsshelf 90 when the penetrator is in the extended position relative to thecannula (FIG. 2B). In some embodiments, recessed portion 86 can beconfigured to maintain the orientation or alignment of enlarged head 58as the penetrator is moved or advanced from the retracted position tothe extended position. For example, in some embodiments, recessedportion 58 has a depth 102 that is at least as large as (e.g., isgreater than, or between any two of: 100, 110, 120, 130, 140, 150, ormore percent of) penetration distance 82 (e.g., such that enlarged head58 is at least partially within recessed portion 86 when distal end 66extends beyond second end 30 of the cannula), and/or enlarged head 58has a transverse dimension (e.g., diameter) that is at least 90% (e.g.,greater than, or between any two of: 90, 92, 94, 96, 98, and/or 100percent) of a corresponding transverse dimension of recessed portion 86(e.g., such that cannula 18 limits tilting of enlarged head 58 relativeto cannula 14, and/or limits misalignment of enlarged head 58 relativeto primary portion 62 of the penetrator).

For example, in the embodiment shown, depth 102 of recessed portion 58is between 175% and 250% (e.g., between 200% and 225%) of penetrationdistance 82. In this embodiment, enlarged head 58 and recessed portion86 each has a circular cross section, and enlarged head 58 has adiameter 106 that is between 90% and 100% (e.g., between 95% and 100%)of diameter 110 of recessed portion 86. In some embodiments, a length114 of enlarged head 58 is at least 150% (e.g., at least, or between anytwo of: 150, 175, 200, 225, 250, 300, or more percent) of penetrationdistance 82. For example, in the embodiment shown, length 114 is over300% of penetration distance 82, such that a portion of enlarged head 58that is at least as long as penetration distance 82 is disposed inrecessed portion 86 when distal end 66 of the penetrator is even withsecond end 30 of the cannula (and the orientation of enlarged head 58relative to cannula 18 is thereby maintained). In some embodiments,enlarged head 58 has an elongated shape such that length 114 is greaterthan (e.g., greater than, or between any two of: 2, 3, 4, 6, 8, or moretimes) diameter 106. For example, in the embodiment shown, length 114 isbetween 8 and 12 times diameter 106.

FIG. 3 depicts a second embodiment 10 a of the present apparatuses.Apparatus 10 a is substantially similar to apparatus 10, with theexception that apparatus 10 a does not include a handle (e.g., handle22).

Embodiments of the present kits can comprise one or more of the presentcannulas (e.g., cannula 14) and a reusable tray or other container in apackage (e.g., a sealed pouch or the like), where both the cannula(s)and the tray are or can be sterilized (and can be re-sterilized inadvance of being re-used). Both the tray and the package may berectangular in shape. In addition, some embodiments of the present kitscan also include two or more penetrators configured to create differentmicrofractures. For example, some embodiments of the present kitscomprise one or more of the present cannulas, a sterlizable tray, afirst penetrator configured to have a penetration distance of between 5mm and 8 mm when used in combination with the cannula, and a secondpenetrator configured to have a penetration distance greater than 8 mmwhen used in combination with the cannula. More specifically, someembodiments of the present kits may include a package (e.g., a box or aflexible package) that comprises sterilized versions of these items.Other embodiments of the present kits comprise one or more of thepresent penetrators (e.g., a single penetrator or two penetrators havingdifferent penetration depths, different tip diameters, different tipshapes, and/or the like) that are sterile and disposed in a package.Embodiments of the present kits may also include, in more specificembodiments, instructions for use, which instructions may be inside thepackage (e.g., as an insert) or outside the package (such as a stickeron the package).

FIGS. 4A and 4B depict an example of the present methods (e.g., usingembodiment 10 a of the present apparatuses). Some embodiments of thepresent methods comprise: disposing an embodiment of the presentmicrofracture apparatuses (e.g., 10, 10 a) adjacent to subchondral boneof a patient (e.g., in the knee, shoulder, or other joint). For example,in the embodiment shown, apparatus 10 a is disposed adjacent tosubchondral bone of articular surface 150 in a patient's knee 154 (e.g.,with second end 30 of cannula 18 in contact with the subchondral bone,as shown). Some embodiments further comprise moving or advancingpenetrator 14 relative to cannula 18 (e.g., from FIG. 4A to FIG. 4B)until distal end 66 of the penetrator extends into the subchondral bone(as in FIG. 4B) to form a microfracture having a depth of at least 5 mm.For example, in the embodiment shown, penetrator 18 is manually advancedsubstantially without rotation of the penetrator by striking orimpacting proximal end 54 of the penetrator with a mallet 158 untildistal end 66 extends into the subchondral bone by a distance of, andforms a microfracture 162 having a depth of, 10 mm. In the embodimentshown, the position of second end 30 of the cannula relative to thesubchondral bone remains substantially constant while advancing thepenetrator into the bone. In some embodiments of the present methods,the apparatus is repeatedly disposed adjacent the bone (e.g., withsecond end 30 of the cannula in contact with the subchondral bone and/orin contact with cartilage, such as, for example, cartilage around theperimeter of a lesion), and the penetrator is repeatedly advanced intothe subchondral bone to form a plurality of microfractures (e.g., havingsubstantially the same depths). In some embodiments, the present methodscan be performed on and/or in the surfaces of other joints, such as, forexample, the shoulder, the ankle, the hip, and/or the patellofemoraljoint within the knee.

Referring now to FIGS. 5A-5C, a second embodiment 14 a of the presentpenetrators is shown. Penetrator 14 a is similar in many respects topenetrator 14. For example, penetrator 14 a has a proximal end 54, aprimary portion 62, a distal end 66 (e.g., pointed distal end 66, asshown), and a penetration portion 70 a adjacent distal end 66. While notshown in FIG. 5A, penetrator 14 a can also include an enlarged head(similar to enlarged head 58 of penetrator 14). In this embodiment,penetration portion 70 a has a length 74 a that is a minority of thelength of penetrator 14 a between proximal end 54 and distal end 66.Similarly, in some embodiments, penetrator 14 a has a transversedimension of less than 1.2 mm (e.g., between 1 mm and 1.1 mm; less than1.1 mm, less than 1.05 mm, less than 1 mm; less than, or between any twoof, 0.5, 0.6, 0.7, 0.8, 0.9, and/or 1 mm). For example, in theembodiment shown, penetration portion 70 a has a circular cross-sectionwith a diameter 78 a of between 1 and 1.2 mm (e.g., 1.04 mm). As withpenetrator 14, penetrator 14 a is configured to be disposed in channel34 of cannula 18 such that penetrator 14 is movable between a (1)retracted position (e.g., in which distal end 66 of the penetrator doesnot extend beyond second end 30 of the cannula) and (2) an extendedposition in which distal end 66 of the penetrator extends beyond secondend 30 of the cannula by a penetration distance 82, which may, forexample, be at least (e.g., greater than) 5 mm (e.g., 7 mm, 8 mm, 8-10mm, more than 10 mm) and/or at least (e.g., greater than) 5 times (e.g.,greater than, or between any two of: 6, 7, 8, 9, 10, or more times) atransverse dimension (e.g., diameter) of penetrator 14 (e.g., diameter78 a of penetration portion 70).

For example, in the embodiment shown, penetration distance 82 is between8 mm and 10 mm (e.g., 10 mm), which is greater than 7 times diameter 78a. In some embodiments, the length of the penetration portion is greaterthan a penetration distance 82 for which the penetrator is designed. Forexample, in the embodiment shown, length 74 a is greater than thepenetration distance 82 (e.g., and greater than the sum of penetrationdistance 82 and the length of distal portion 42 of cannula 14 and/orcannula 14 a). In the embodiment shown, diameter 50 of primary portion38 is larger than diameter 78 a of penetration portion 70 a, and/orequal to or greater than 1.2 mm (e.g., substantially equal to 1.27 mm)and/or less than 2.0 mm. In some embodiments, diameter 50 is also lessthan 1.2 mm (e.g., between 1 mm and 1.1 mm, less than 1.1 mm, less than1.05 mm). In some embodiments, diameter 50 is substantially equal todiameter 78.

In some embodiments, penetrator 14 comprises a central wire definingtransverse dimension 78 a that is encircled or encased by an outertubing (e.g., metallic tubing, plastic shrink wrap, and/or the likealong the length of primary portion 62 a to define transverse dimension50 a.

As shown in FIGS. 5B and 5C, however, penetration portion 70 a differsfrom penetration portion 70 in that penetration portion 70 a isconfigured to reduce (e.g., relative to that of penetration portion 70)the force required to insert distal end 66 into a bone, and to reduce(e.g., relative to that of penetration portion 70) the force required toremove distal end 66 from the bone. For example, in the embodimentshown, penetration portion 70 includes a narrow portion 200 betweendistal end 66 and primary portion 62, with narrow portion 200 beingnarrower in at least one transverse dimension than primary portion 62.In this embodiment, narrow portion 200 is configured to reduce thesurface area of penetration portion 70 a that is in contact with bonewhen the penetration portion is driven into a bone. For example, theenlarged part of penetration portion 70 a adjacent distal end 66 (andcorresponding to first transverse dimension 78 a) creates a path throughthe bone during insertion that is larger than narrow portion 200, suchthat at least a part of narrow portion 200 is not (at least initially)in contact with the bone. Even if penetration portion 70 a remains inthe bone for a sufficient time for the bone to rebound towards narrowportion 200, the reduced transverse dimension of narrow portion 200 mayreduce the interface pressure between the penetrator and the reboundedbone material. This reduced contact and/or reduced interface pressurecan reduce the force required to remove distal end 66 from the bone(e.g., relative to the force required to remove from the same type ofbone penetration portion 70 of penetrator 14, which has a circularcylindrical shape with constant diameter and cross-section along thelength of penetration portion 70—i.e., does not include narrow portion200).

For example, in the embodiment shown, transverse dimension 78 a is afirst transverse dimension in the penetration portion, and a secondtransverse dimension 204 that is smaller than first transverse dimension78 a is between primary portion 62 and first transverse dimension 78 a(in penetration portion 70 a, as shown). In some embodiments, secondtransverse dimension 204 is substantially constant along part of length74. For example, in the embodiment shown, narrow portion 200 has alength 208 along which second transverse dimension 204 is substantiallyconstant. In the embodiment shown, length 208 is between 20 percent and35 percent of length 74 a of penetration portion 70 a. In otherembodiments, length 208 can be any suitable fraction or percentage oflength 74 a (e.g., less than any one of, or between any two of, 5, 10,15, 20, 25, 30, 35, 40, 45, and/or 50 percent). In some embodiments,first transverse dimension 78 a is adjacent distal end 66 (i.e., closerto distal end 66 than to primary portion 62). For example, in theembodiment shown, the distance between distal end 66 and narrow portion200 is less than length 208 of the narrow portion. In other embodiments,narrow portion can be disposed at any suitable position along the lengthof penetration portion 70 a. In the embodiment shown, penetrationportion 70 a further includes a third transverse dimension 212 betweennarrow portion 200 and primary portion 62. In this embodiment, thirdtransverse dimension 212 is substantially equal to first transversedimension 78 a, but may differ in other embodiments. In the embodimentshown, third transverse dimension is substantially constant along aproximal segment 214 of penetration portion 70 a.

In some embodiments, penetrator 14 a has a first cross-sectional shapeand/or area at first transverse dimension 78 a, a second cross-sectionalshape and/or area at second transverse dimension 204, and the firstcross-sectional shape and/or area is larger than (e.g., and, as shown,concentric to) the second cross-sectional shape and/or area. Forexample, in the embodiment shown, penetrator 14 a has a first circularcross section at first transverse dimension 78 a, and a second circularcross section at second transverse dimension 204 (e.g., with the firstcircular cross-section being substantially concentric with the secondcircular cross-section, as shown). In this embodiment, penetrator 14 aalso has a circular cross-section at third transverse dimension 212. Inother embodiments, the penetrator, the penetration portion, and/or thenarrow portion can have any suitable cross-sectional shapes (e.g.,circle, square, triangular, rectangular, star, and/or the like), whethersimilar or dissimilar (e.g., the cross-sectional shape of the narrowportion may differ from the cross-sectional shape of the remainder ofthe penetration portion), such that the cross-sectional shape of thesurface of area of the narrow portion that contacts bone duringinsertion is reduced. For example, in some embodiments, the penetrationportion can have a circular cross-section and the narrow portion canhave a rectangular cross-section. In other embodiments, narrow portion200 may be fluted.

In the embodiment shown, penetration portion 70 a also differs frompenetration portion 70 in that distal end 66 is configured to reduce(e.g., relative to that of penetration portion 70) the force required toinsert distal end 66 into a bone, and to reduce (e.g., relative to thatof penetration portion 70) the force required to remove distal end 66from the bone. For example, in the embodiment shown, distal end 66includes a pointed tip 216 with a cross-sectional shape defined by a tipangle 220 of 60 degrees or greater (e.g., substantially equal to 60degrees, as shown). For example, in the embodiment shown, pointed tip216 has a conical shape having a cross-sectional shape that is bisectedby a central longitudinal axis 224 of penetration portion 70 a. In otherembodiments, pointed tip 216 can have any suitable shape (e.g., atriangular or rectangular pyramid). In some embodiments, tip angle 220is greater than 60 degrees, greater than 90 degrees, and/or greater than120 degrees (e.g., equal to 180 degrees, or substantially perpendicularto a longitudinal axis of an adjacent portion of penetration portion 70a). For example, a tip angle 220 of 60 degrees, as shown, reduces thelength of the cone that defines pointed tip relative to the 30 degreetip angle of penetrator 14, and thereby reduces the surface area of thecone that is available to contact bone during insertion and removal.Likewise, further increases in tip angle 220 will further reduce thesurface area of a conical pointed that is available to contact bone. Inthe embodiment shown, penetration portion 70 a further includes a firstradiused portion 228 (which may instead be linearly tapered) betweenpointed tip 216 (and first transverse dimension 78 a) and narrow portion200, and a second tapered portion 232 (which may instead be radiused)between proximal segment 214 and narrow portion 200, to reducelikelihood of the transitions in transverse dimension resulting inpoints along penetration portion 70 a that might otherwise catch orresist insertion or removal of distal end 66 into or from bone. In otherembodiments, the tip can be rounded and/or can be defined by a single(e.g., planar) facet extending across the entire cross-section of thepenetration portion.

In the embodiment shown, penetrator 14 a is substantially straight priorto being disposed in channel 34 of cannula 18 or cannula 18 b, such thatinserting the penetrator into the cannula causes the penetration portion70 a of the penetrator to bend within channel 34 (between primaryportion 38 or 38 a and distal portion 42 or 42 a). In some suchembodiments, penetrator 14 a may be resilient enough to (e.g., at leastpartially) return to its straight shape after removal from the cannula.

FIG. 6 depicts a side cross-sectional view of a second embodiment 18 aof the present cannulas. Cannula 18 a is similar in many respects tocannula 18. For example, cannula 18 a has a first end 26, a second end30, and a channel 34 extending between the first end and the second end.Such first and second ends should be understood as the locations of thebeginning and end of the channel. In this embodiment, cannula 18 has aprimary portion 38 a and a distal portion 42 a, with primary portion 38a extending between first end 26 and distal portion 42 a (e.g., amajority of the length of the cannula, as in the embodiment shown), andwith distal portion 42 a extending between primary portion 38 and secondend 30. In the embodiment shown, cannula 18 a differs from cannula 18 inthat in cannula 18 a, distal portion 42 a is not angled relative toprimary portion 38 a (distal portion 42 a and primary portion 38 a sharea common central longitudinal axis). Primary portion 38 a has atransverse dimension 300 (e.g., a diameter, in the embodiment shown). Inthe embodiment shown, distal portion 42 a is tapered between primaryportion 38 a and second end 30, as shown. In this embodiment distalportion 42 a has a length 304 that is less than a length 308 of cannula18 a (e.g., less than 20 percent of length 308). In other embodiments,the relative lengths of primary portion 38 a and distal portion 42 a canbe any suitable sizes for various procedures and/or for patients ofvarious ages and/or sizes. In some embodiments of the present methods,cannula 18 a is bent to form a cannula with an angled distal portion, asdescribed below.

Referring now to FIGS. 7A and 7B, side cross-sectional views are shownof a third embodiment 18 b of the present cannulas. Cannula 18 b issubstantially similar to cannula 18, with the exception that angle 46 bis substantially equal to 15 degrees. In some embodiments, angle 46 bcan be between 5 degrees and 20 degrees (e.g., substantially equal toeither of, or between, 10 degrees and 15 degrees). In other embodiments,angle 46 b can be greater than 60 degrees (e.g., equal to, or betweenany two of: 60, 70, 80, 90, and/or more degrees). As a further example,distal portion 42 b can include a curved or hooked shape such that angle46 b is effectively larger than 90 degrees (e.g., equal to, or betweenany two of: 90, 120, 150, 180, and/or 180 degrees).

FIGS. 7A and 7B also include dimensions (in inches) for at least oneexemplary embodiment of the present cannulas. Further, the differencebetween cannula 18 a of FIG. 6 and cannula 18 b of FIGS. 7A and 7Billustrate an embodiment of the present methods. In particular, someembodiments of the present methods (e.g., of making the presentcannulas) comprise forming cannula 18 b by bending (e.g., with a jig orthe like) cannula 18 a to angle 46.

FIGS. 8A-8C depict various views of handle 22. FIG. 8B includesdimensions (in inches) for at least one exemplary embodiment of thepresent handles. As shown, handle 22 comprises a central longitudinalpassage 312 configured to receive part of a primary portion (e.g., 38,38 a) of a cannula (e.g., 18, 18 a, 18 b), such as, for example, via apress fit or the like.

FIG. 9 depicts an exploded perspective view of a kit 400 comprising anembodiment 10 of the present apparatuses and a package 404 for theapparatus. In the embodiment shown, package 404 comprises a lower panel408, a foam or other (e.g., molded plastic) receptacle 412 configured toreceive apparatus 10 (including penetrator 14 and cannula 18), and anupper panel 416. In the embodiment shown, kit 400 also includesinstructions 420 and a box 424. As indicated by the arrangement ofpanels 408 and 416, receptacle 412, and instructions 420, thesecomponents fit into box 424. In some embodiments, such as the one shown,cannula 18 (including handle 22) and/or penetrator 14 are sterile and/orsealed in plastic independently of receptacle 412.

FIGS. 10A-10D depict various views of another embodiment 10 b of thepresent apparatuses that includes a penetrator removal tab 500 incombination with a penetrator 14 b and a fourth embodiment 18 c of thepresent cannulas. In the embodiment shown, tab 500 comprises a body 504with a first end 508, a second end 512, a distal side 516, and aproximal side 520. In the embodiment shown, distal side 516 isconfigured to face toward second end 30 of cannula 18 c, and comprises aprotrusion 524 configured to contact handle 22 to act as a fulcrumduring use, as described in more detail below. In the embodiment shown,distal side 520 includes a plurality of grooves 528 to contact andresist slippage of a user's thumb during use. In other embodiments,grooves 528 may be omitted and/or substituted with a different type oftexture. As shown in FIGS. 10C and 10D, body 504 has a curved or arcuateshape such that distal side 516 is concave and proximal side 520 isconvex.

In the embodiment shown, body 504 includes an elongated opening 532 thatis closer to first end 508 than to second end 512, and that isconfigured to receive enlarged head 58 of penetrator 14 a as shown inFIGS. 10B and 10C. For example, in some embodiments, opening 516 canhave a width (smaller transverse dimension) that is between 100% and150% (e.g., between any two of: 100%, 110%, 120%, 130%, 140%, and 150%)of a corresponding transverse dimension (e.g., diameter 106) of enlargedhead 58, and/or can have a height (larger transverse dimension) that isbetween 150% and 250% (e.g., between any two of: 150%, 175%, 200%, 225%,and 250%) of a corresponding transverse dimension (e.g., diameter 106)of enlarged head 58. The elongated shape of opening 532 permits tab 500to pivot relative to enlarged head 58 (and overall penetrator 14 b) toapply an axial removal force to penetrator 14 b while minimizing anylateral force that might otherwise deflect and/or impede movement of thepenetrator.

As shown, proximal side 520 of body 504 also includes a recess 536configured to at least partially receive FIG. 10C) a correspondingflange 542 that is coupled to (e.g., unitary with) enlarged head 58. Forexample, in the embodiment shown, flange 542 is configured to bedisposed over and coupled in fixed relation to proximal end 54 andenlarged head 58 of penetrator 14 b. In his embodiment, flange 542includes a neck 546 configured to be crimped and/or adhered via adhesiveto enlarged head 58. In other embodiments, flange 542 may be unitarywith enlarged head. As shown, flange 542 has a transverse dimension(e.g., diameter) that is larger than a corresponding transversedimension (e.g., diameter) of opening 504 but smaller than acorresponding transverse dimension of recess 536. In some embodiments,enlarged head 58 is omitted and flange 542 and opening 528 (e.g., andrecess 532) also limits the maximum penetration distance 82.

In use, a penetrator 14 b (e.g., having flange 542 coupled to enlargedhead 58) can be inserted through opening 528 and into cannula 18 c suchthat tab 500 is disposed between flange 542 and handle 22 a of cannula18 c. Second end 30 of cannula 18 c can then be disposed in a desiredlocation relative to a bone, and penetrator 14 b can be impacted todrive distal end 66 of the penetrator into the bone. With distal end 66disposed in the bone, a user can apply a force to proximal side 520 oftab 500 in direction 550 (toward second end 30 of cannula 18 c) to causetab 500 to pivot around protrusion 524 and apply a force to flange 542to retract the penetrator in direction 524. In the embodiment shown,protrusion 524 is sized such that a second part of tab 500 (504) willalso contact handle 22 a at point 558 (such that protrusion once thepenetrator is retracted by a distance about equal to or just larger thanthe maximum penetration distance (e.g., 82 of FIG. 2C) of thepenetrator/cannula combination to prevent protrusion 524 from furtheracting as a fulcrum for tab 500. For example, limiting the retractiondistance (e.g., to between 100% and 120% of maximum penetration distance82) in this way can minimize the lateral force applied to enlarged head58 during retraction of the penetrator and can facilitate reinsertion ofthe penetrator in a new location by minimizing the distance thepenetrator must be advanced to bring its distal end (66) into initialcontact with the bone at the new location.

In the embodiment shown, handle 22 a is substantially similar to handle22 with the exception that handle 22 a includes a protrusion 562 that isaligned with distal portion 42 of cannula 18 c. For example, in thisembodiment, primary portion 38 of cannula 18 c, distal portion 42 ofcannula 18 c, and protrusion 562 of handle 22 d are each bisected by asingle common plane. Protrusion 562 thus provides an indicator for auser of the orientation of distal portion 42 (e.g., even when distalportion 42 is disposed within a patient and out of the user's sight). Inother embodiments, any suitable indicator may be used (e.g., adepression instead of a prorusion, an arrow printed or painted on handle22, and/or the like).

FIG. 11A depicts a cross-sectional view of a portion of a fourthembodiment 18 d of the present cannulas, and FIG. 11B depicts across-sectional view of the same portion of cannula 18 d with apenetrator 14 a disposed in channel 34 a of the cannula. Cannula 18 d issubstantially similar to cannula 18 b, with the exception that channel34 a cannula 18 d includes a first transverse dimension 600 betweenfirst end (i.e., 26) and second end 30, and a second transversedimension 604 at second end 30 that is smaller than first transversedimension 600. In the embodiment shown, channel 34 a also has a thirdtransverse dimension 608 at a proximal end of distal portion 42 a thatis larger than second transverse dimension 604. Third transversedimension 608 may, for example, be substantially equal to firsttransverse dimension 600. For example, in the embodiment shown, channel34 a has a circular cross-section with a diameter 600 that issubstantially constant along a majority of the length of channel 34 a.

In the embodiment shown, second transverse dimension 604 issubstantially constant along a portion 612 having a length 616. In someembodiments, such as the one shown, length 616 is greater than secondtransverse dimension 604 and is also greater than first transversedimension 600. In this embodiment, second transverse dimension 604 islarger than transverse dimension 78 a of penetrator 14 a, but secondtransverse dimension 604 is closer in size to transverse dimension 78 athan to first transverse dimension 600. As with cannula 18 b, transversedimension 604 is large enough to permit penetration portion 70 a ofpenetrator 14 a to laterally flex (e.g., away from the center of thechannel and toward to the center of curvature) around the bend or anglebetween primary portion 38 a and distal portion 42 a of cannula 18 d. Inthis embodiment, however, the smaller second transverse dimension 604(smaller relative to first transverse dimension 600) is configured tominimize lateral flexure of penetration portion 70 a of penetrator 14 aduring insertion into and removal from bone (e.g., to ensure thatmicrofractures are substantially circular rather than oval).

FIG. 12 depicts a cross-sectional view of a portion of cannula 18 b(FIGS. 7A-7B) with a guide member 620 coupled to distal or second end 30of the cannula. In this embodiment, channel 34 of cannula 18 b has afirst transverse dimension 624 at second end 30 of the cannula. In thisembodiment, guide member 620 has an opening 628 and is configured to becoupled to second end 30 of the cannula such that at least a portion ofopening 628 is aligned with channel 34. In this embodiment, opening 628has a transverse dimension 632 that is smaller than transverse dimension624 of channel 34 at second end 30 of the cannula. In the embodimentshown, channel 34 also has a second transverse dimension 636 at aproximal end of distal portion 42 a that is larger than transversedimension 632 of opening 628. Second transverse dimension 636 may, forexample, be substantially equal to first transverse dimension 624. Forexample, in the embodiment shown, channel 34 has a circularcross-section with a diameter 624 that is substantially constant along amajority of the length of channel 34.

In the embodiment shown, second transverse dimension 628 issubstantially constant along a portion 640 having a length that is lessthan (e.g., equal to or greater than 40%, 50%, or a greater percentageof) transverse dimension 632. In this embodiment, transverse dimension632 is larger than transverse dimension 78 a of penetrator 14 a, buttransverse dimension 632 is closer in size to transverse dimension 78 athan to first transverse dimensions 624. Transverse dimension 624 and632 are large enough to permit penetration portion 70 a of penetrator 14a to laterally flex (e.g., away from the center of the channel andtoward to the center of curvature) around the bend or angle betweenprimary portion 38 a and distal portion 42 a of cannula 18 b. In thisembodiment, however, the smaller transverse dimension 632 (smallerrelative to first transverse dimension 624) is configured to minimizelateral flexure of penetration portion 70 a of penetrator 14 a duringinsertion into and removal from bone (e.g., to ensure thatmicrofractures are substantially circular rather than oval).

FIG. 13 depicts a cross-sectional view of a portion of cannula 18 b withanother embodiment 14 c of the present penetrators disposed in channel34 of the cannula. Penetrator 14 c is substantially similar topenetrator 14 a with the exception that penetration portion 70 b ofpenetrator 14 c includes a guide portion 644 spaced from distal end 66(by a distance at least as large as the desired penetration distance)and having a transverse dimension 648 that is larger than transversedimension 204 of penetration portion 70 b. In the embodiment shown,guide portion 644 includes two segments 654 spaced apart from each otherand each having a transverse dimension 648 that is larger than thesmallest transverse dimension 204 of penetrator 14 c. In thisembodiment, segments 654 are spaced apart from each other by a distance658 that is configured to permit segments 654 to pass through the curvein channel 34 between proximal portion 38 a and distal portion 42 a ofcannula 18 b. For example, in the embodiment shown, distance 658 isgreater than transverse dimension 624 of channel 34, and is greater thelength of each segment 654.

In the embodiment shown, each segment 654 also has a length that isequal to or greater than their transverse dimension 648. The elongatedouter profile of segments 654 resists longitudinal rotation of eachindividual segment and thereby resist lateral flexure and misalignmentof penetration portion 70 b. In other embodiments, each segment 654 canhave a length that is equal to or greater than 40%, 50%, or a greaterpercentage of transverse dimension 648. In the embodiment shown, eachsegment 654 has a circular cross-sectional shape, but in otherembodiments may have any suitable cross-sectional shape (e.g.,triangular, square, star-shaped with three, four, five, or more points,and/or any other shape that permits the apparatus to function asdescribed). In this embodiment, transverse dimension 648 can be equal toor larger than transverse dimension 78 a of penetrator 14 c, buttransverse dimension 648 is closer in size to transverse dimension 624than to transverse dimension 204. The configuration (including distancefrom distal end 66, shape, and transverse dimension 648) of guideportion 640 is such that guide portion 640 will slide through channel 34past the bend between proximal portion 38 a and distal portion 42 a, butwill also maintain axial alignment of the part of penetration portion 70b between guide portion 640 and distal end 66 when guide portion 640 islocated entirely in distal portion 42 a. In this embodiment, the largertransverse dimension 648 (larger relative to transverse dimension 204)is configured to minimize lateral flexure of penetration portion 70 b ofpenetrator 14 c during insertion into and removal from bone (e.g., toensure that microfractures are substantially circular rather than oval).

FIG. 14A depicts a side view of a fifth embodiment 18 e of the presentcannulas, and FIG. 14B depicts an enlarged side view of cannula 18 e.Cannula 18 e is similar in several respects to cannula 18 b with theprimary exception that second end 30 (and the corresponding second endof channel 34) is aligned with first end 26 (and the corresponding firstend of the channel) and/or with longitudinal axis 662 of primary portion38 c. In the embodiment shown, distal portion 42 c is longer than distalportion 42 a of cannula 18 a to accommodate a relatively large curvedportion that curves in a first direction away from axis 662 and thencurves back toward axis 662 to a linear portion that terminates atsecond end 30. In this embodiment, distal portion 42 c includes aplurality of curved segments and, more particularly, includes an arcuatefirst segment 666 extending from a distal end of primary portion 38 c,an arcuate second segment 670 extending from and curving in a directionopposite to the curvature of arcuate first segment 666, an arcuate thirdsegment 674 extending from and curving in the same direction as thecurvature of arcuate second segment 670, and a linear fourth segment 678extending from arcuate third segment 674, as shown. In this embodiment,a longitudinal axis 682 of linear fourth segment 678 intersects axis 662of primary portion 38 c at second end 30 of the cannula. In theembodiment shown, arcuate second segment 670 and third arcuate segment674 each has a radius of curvature that is larger than that of firstarcuate segment 666.

In the embodiment shown, angle 46 c between second end 30 (axis 682) andfirst end 26 (axis 662) is greater than angle 46 b (FIG. 7B). Thedepicted configuration in which distal portion 42 c curves away from andthen back toward the longitudinal axis (662) of primary portion 38 cpermits larger values of angle 46 c while still permitting a penetratorto advance and retract within in the cannula. Angle 46 c can, forexample, be equal to or greater than any one of, and/or between any twoof: 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, or more degrees). Inaddition to permitting greater tip angles, the alignment of second end30 with first end 26 (and/or with longitudinal axis 662) has shownthrough experimentation to make the apparatus (especially with greatertip angles) easier to use. For example, because second end 30 is alignedwith first end 26, an impact force or impulse applied to a proximal endor head of a penetrator within cannula 18 e is directed in a straightline (axis 662) on which second end 30 lies. The effect is to make theapparatus easier to control during use, resulting in more consistent,round microfractures (as opposed to oval microfractures ormicrofractures that are misplaced due to sliding of the cannula.

FIG. 15A and FIG. 15B depict perspective views of a sixth embodiment ofthe present apparatuses having a cannula 18 f, and shown with an adapter700 configured to couple cannula 18 f to a fluid source (e.g., asyringe). The sixth embodiments is substantially similar to the fifthembodiment with the primary exception that distal end 30 of cannula 18 fis disposed at a smaller angle relative to first end 26 thancorresponding angle 46 c of cannula 18 e of FIGS. 14A and 14B.

In the embodiment shown, adapter 700 is includes a first end 704configured to be coupled to (e.g., inserted into) first end 26 ofcannula 18 f and a second end 708 configured to be coupled to a fluidsource, and a channel extending between first end 704 and second end 708to facilitate delivery of a fluid via distal end 30 of the cannula(e.g., to a microfracture in an articular surface of a patient). In thisembodiment, first end 704 includes a tapered, frusto-conical outersurface sized to fit into the channel at first end 26 of cannula 18 f.In some embodiments, the channel of adapter 700 has an inner diameter of5 mm or smaller (e.g., less than 4 mm, 3 mm, 2 mm, or smaller) and/oradapter 700 has at least one outer diameter (e.g., the smallest outerdiameter of tapered first end 704) of less than 6 mm to facilitateinsertion of first end 704 into the channel of cannula 18 f at first end26.

In the embodiment shown, adapter 700 includes protrusions 712 tofacilitate manipulation of the adapter by a user (e.g., to connect theadapter to the cannula or to the fluid source). In the embodiment shown,protrusions 712 extend outwardly at least 3 mm from an adjacent exteriorsurface of adapter 700. Protrusions 712 can also be configuredfacilitate mechanized manipulation of adapter 700. For example, asurgical robot may engage the protrusions to couple adapter 700 to afluid source and/or the cannula.

As shown, adapter 700 can be configured to be coupled to a syringe 716.Other fluid sources may also or alternatively be used (e.g., drip bagsor tubing). In the embodiment shown, second end 708 of adapter 700includes a threads (e.g., a luer lock or luer fitting) configured to becoupled to corresponding threads (e.g., luer lock or luer fitting) 720of the syringe.

Adapter 700 is especially suited to enable delivery (e.g., in some ofthe present methods) of fluids to an articular surface of a patient(e.g., via one of the present cannulas), such as, for example, to amicrofracture in an articular surface of a patient. Examples of fluidsthat may be delivered include saline, hyaluronic acid,platelet-rich-plasma, human tissue allografts such as those derived fromamniotic fluid and/or membranes, growth factors, proteins, and/orcellular-based therapies.

The above specification and examples provide a complete description ofthe structure and use of exemplary embodiments. Although certainembodiments have been described above with a certain degree ofparticularity, or with reference to one or more individual embodiments,those skilled in the art could make numerous alterations to thedisclosed embodiments without departing from the scope of thisinvention. As such, the various illustrative embodiments of the presentdevices are not intended to be limited to the particular formsdisclosed. Rather, they include all modifications and alternativesfalling within the scope of the claims, and embodiments other than theone shown may include some or all of the features of the depictedembodiment. For example, penetrator 18 and/or channel 34 can have anysuitable cross-sectional shape (e.g., triangular, square, rectangular,and/or the like) that permits the present apparatuses and methods tofunction as described in this disclosure. For example, components may becombined as a unitary structure, and/or connections may be substituted.Further, where appropriate, aspects of any of the examples describedabove may be combined with aspects of any of the other examplesdescribed to form further examples having comparable or differentproperties and addressing the same or different problems. Similarly, itwill be understood that the benefits and advantages described above mayrelate to one embodiment or may relate to several embodiments.

The claims are not intended to include, and should not be interpreted toinclude, means-plus- or step-plus-function limitations, unless such alimitation is explicitly recited in a given claim using the phrase(s)“means for” or “step for,” respectively.

The invention claimed is:
 1. An apparatus comprising: a cannula having afirst end, a second end, and a channel extending between the first endand the second end, the channel having a first transverse dimensionbetween the first end and the second end, a second transverse dimension,and a third transverse dimension positioned between the first transversedimension and the second transverse dimension; and a penetrator having adistal end and a first transverse dimension, the penetrator configuredto be disposed in the channel of the cannula such that the penetrator ismovable between a retracted position and an extended position in whichthe distal end extends beyond the second end of the cannula by apenetration distance; and where the channel is tapered from the thirdtransverse dimension toward the second end.
 2. The apparatus of claim 1,where the second transverse dimension is at the second end of thecannula.
 3. The apparatus of claim 1, where: the third transversedimension is larger than the second transverse dimension; or the secondtransverse dimension is smaller than the first transverse dimension. 4.The apparatus of claim 1, where: the third transverse dimension is lessthan the first transverse dimension; and the second transverse dimensionis closer to the second end than the first transverse dimension is tothe second end.
 5. The apparatus of claim 1, where a first taperedportion of the channel that is tapered from the third transversedimension toward the second end is tapered such that the thirdtransverse dimension of the channel decreases as the channel extendstoward the second end of the cannula.
 6. The apparatus of claim 5, wherethe channel defines a first portion between the first tapered portion ofthe channel and the second end.
 7. The apparatus of claim 6, where asecond tapered portion of the channel is tapered from the first portiontoward the second end such that a transverse dimension of the channelincreases as the channel extends from the first portion toward thesecond end of the cannula.
 8. The apparatus of claim 1, where thepenetrator is configured to be moved from the retracted position to theextended position to form a microfracture.
 9. The apparatus of claim 1,where the penetrator is configured to be moved from the retractedposition to the extended position substantially without rotation of thepenetrator.
 10. An apparatus comprising: a cannula having a firstportion, a second portion, and a channel extending between the firstportion and the second portion, the channel having a first transversedimension between the first portion and the second portion, a secondtransverse dimension at the second portion that is smaller than thefirst transverse dimension, and a third transverse dimension positionedbetween the first transverse dimension and the second transversedimension; and a penetrator having a distal end and a first transversedimension, the penetrator configured to be disposed in the channel ofthe cannula such that the penetrator is movable between a retractedposition and an extended position in which the distal end extends beyondthe second portion of the cannula by a penetration distance; and whereat least a portion of the channel is tapered from the third transversedimension toward the second transverse dimension.
 11. The apparatus ofclaim 10, where the third transverse dimension is substantially equal tothe first transverse dimension of the channel.
 12. The apparatus ofclaim 10, the second transverse dimension is positioned at an end of thecannula.
 13. The apparatus of claim 10, where the penetrator isconfigured to be moved from the retracted position to the extendedposition substantially without rotation of the penetrator to form insubchondral bone a microfracture.
 14. The apparatus of claim 10, where:a second portion of the channel is disposed at an angle relative to afirst portion of the channel; and the second portion of the channelincludes the portion of the channel that is tapered from the thirdtransverse dimension towards the second transverse dimension such that across-sectional area of the channel decreases as the channel extendstoward an end of the cannula.
 15. The apparatus of claim 14, where thethird transverse dimension is less than the first transverse dimensionof the channel.
 16. The apparatus of claim 14, where the second portionof the cannula includes a second tapered portion of the channel that istapered from the end of the cannula toward the first portion such that across-sectional area of the second tapered portion of the channelincreases as the channel extends toward the end of the cannula.
 17. Amethod of forming a microfracture in subchondral bone of a patient, themethod comprising: disposing the apparatus of claim 1 adjacent to thesubchondral bone; and advancing the penetrator relative to the cannula,substantially without rotation of the penetrator, until the distal endof the penetrator extends into the subchondral bone to form amicrofracture.
 18. The method of claim 17, further comprising: repeatingthe steps of disposing and advancing to form a plurality ofmicrofractures in the subchondral bone; and where the steps of advancingis performed while the apparatus is in contact with the sub chondralbone.
 19. The method of claim 18, further comprising: actuating apenetrator removal tab coupled to the penetrator to retract the distalend of the penetrator from the subchondral bone.
 20. The method of claim17, further comprising: removing the penetrator from the cannula; andinjecting a solution to the microfracture through the channel of thecannula.